Ok, ok.
The truth now.
Every year, each department has a fixed amount of money for increments and bonuses.
Forget that BS about "if you perform well, you will be rewarded handsomely" crap.
Unless your colleagues are all bumbling idiots and you are the only star performer (ok, everybody thinks he or she IS the company's star performer but I digress
), your bonus is more or less fixed and will likely be similar to what your colleagues are getting, some slightly more, some slightly less.
And if you think you deserve a promotion with a big increment just because your colleague is getting one, think again. The fcuking pie is limited and every year, maybe only one person in the department will be promoted because that is about all the money the company can dish out for increments.
Split the increment loot between the both of you? Both of you will cringe at the miserly increment.
Better to make one happy than both hopping mad.
Really.